Myocardial clearance of I-123 metaiodobenzylguanidine in dilated cardiomyopathy.
We present the results of sequential imaging studies conducted in two patients with dilated cardiomyopathy whose responses to long-term beta-blocker therapy differed. We evaluated the time course of the myocardial clearance and the heart to upper mediastinal ratios of I-123 metaiodobenzylguanidine (MIBG) scintigraphy. In the first patient, the left ventricular ejection fraction as well as the clinical symptoms were improved by long-term beta-blocker therapy with a concurrent normalization of the myocardial clearance and the heart to upper mediastinal ratio of I-123 MIBG scintigraphy. The myocardial clearance and the upper mediastinal ratio of I-123 MIBG indicated no improvement in the second patient, and the left ventricular function did not change. The myocardial clearance and the heart to upper mediastinal ratio of I-123 MIBG scintigraphy were useful in evaluating the efficacy of long-term beta-blocker therapy in patients with dilated cardiomyopathy.
Yamanari
H
H
Department of Cardiovascular Medicine, Okayama University Medical School, Japan.
Sakamoto
T
T
Takenaka
S
S
Saito
H
H
Koyama
S
S
Ohe
T
T
D019797:3-Iodobenzylguanidine / Q000493:pharmacokinetics; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging* / Q000378:metabolism; D015902:Gamma Cameras; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D009206:Myocardium / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation / Q000379:methods
D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine